A variety of different operations may be applied to manipulate image data. One such example is a matting operation, in which image data for a single image is decomposed into a foreground image and a background image. A result of the matting operation may be used for a variety of different purposes, such as to extract a foreground object for placement with a different background image.
Some pixels in the image, however, may be a combination of the foreground and background images, which is describable by an alpha value as a linear combination of the images. These pixels are often referred to as mixed pixels and are typically found along an edge between the foreground and background image. Conventional matting operations, however, could result in errors in describing a correct fraction of the background and foreground images to be used for these pixels. Consequently, these conventional matting operations could result in errors, which may be viewable by a user as halos, an appearance that the foreground image was cut out manually using scissors, and so on.